RandomHuman
/
Mypal
1
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity
Mypal/dom/security/SRICheck.cpp

543 lines
19 KiB
C++
Raw Permalink Blame History

/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#include "SRICheck.h"
#include "mozilla/Base64.h"
#include "mozilla/LoadTainting.h"
#include "mozilla/Logging.h"
#include "mozilla/Preferences.h"
#include "mozilla/dom/SRILogHelper.h"
#include "mozilla/dom/SRIMetadata.h"
#include "nsContentUtils.h"
#include "nsIChannel.h"
#include "nsIConsoleReportCollector.h"
#include "nsIProtocolHandler.h"
#include "nsIScriptError.h"
#include "nsIIncrementalStreamLoader.h"
#include "nsIUnicharStreamLoader.h"
#include "nsIURI.h"
#include "nsNetUtil.h"
#include "nsWhitespaceTokenizer.h"
#define SRIVERBOSE(args) \
MOZ_LOG(SRILogHelper::GetSriLog(), mozilla::LogLevel::Verbose, args)
#define SRILOG(args) \
MOZ_LOG(SRILogHelper::GetSriLog(), mozilla::LogLevel::Debug, args)
#define SRIERROR(args) \
MOZ_LOG(SRILogHelper::GetSriLog(), mozilla::LogLevel::Error, args)
namespace mozilla {
namespace dom {
/**
* Returns whether or not the sub-resource about to be loaded is eligible
* for integrity checks. If it's not, the checks will be skipped and the
* sub-resource will be loaded.
*/
static nsresult
IsEligible(nsIChannel* aChannel, mozilla::LoadTainting aTainting,
const nsACString& aSourceFileURI,
nsIConsoleReportCollector* aReporter)
{
NS_ENSURE_ARG_POINTER(aReporter);
if (!aChannel) {
SRILOG(("SRICheck::IsEligible, null channel"));
return NS_ERROR_SRI_NOT_ELIGIBLE;
}
// Was the sub-resource loaded via CORS?
if (aTainting == LoadTainting::CORS) {
SRILOG(("SRICheck::IsEligible, CORS mode"));
return NS_OK;
}
nsCOMPtr<nsIURI> finalURI;
nsresult rv = NS_GetFinalChannelURI(aChannel, getter_AddRefs(finalURI));
NS_ENSURE_SUCCESS(rv, rv);
nsCOMPtr<nsIURI> originalURI;
rv = aChannel->GetOriginalURI(getter_AddRefs(originalURI));
NS_ENSURE_SUCCESS(rv, rv);
nsAutoCString requestSpec;
rv = originalURI->GetSpec(requestSpec);
NS_ENSURE_SUCCESS(rv, rv);
if (MOZ_LOG_TEST(SRILogHelper::GetSriLog(), mozilla::LogLevel::Debug)) {
SRILOG(("SRICheck::IsEligible, requestURI=%s; finalURI=%s",
requestSpec.get(),
finalURI ? finalURI->GetSpecOrDefault().get() : ""));
}
// Is the sub-resource same-origin?
if (aTainting == LoadTainting::Basic) {
SRILOG(("SRICheck::IsEligible, same-origin"));
return NS_OK;
}
SRILOG(("SRICheck::IsEligible, NOT same origin"));
NS_ConvertUTF8toUTF16 requestSpecUTF16(requestSpec);
nsTArray<nsString> params;
params.AppendElement(requestSpecUTF16);
aReporter->AddConsoleReport(nsIScriptError::errorFlag,
NS_LITERAL_CSTRING("Sub-resource Integrity"),
nsContentUtils::eSECURITY_PROPERTIES,
aSourceFileURI, 0, 0,
NS_LITERAL_CSTRING("IneligibleResource"),
const_cast<const nsTArray<nsString>&>(params));
return NS_ERROR_SRI_NOT_ELIGIBLE;
}
/* static */ nsresult
SRICheck::IntegrityMetadata(const nsAString& aMetadataList,
const nsACString& aSourceFileURI,
nsIConsoleReportCollector* aReporter,
SRIMetadata* outMetadata)
{
NS_ENSURE_ARG_POINTER(outMetadata);
NS_ENSURE_ARG_POINTER(aReporter);
MOZ_ASSERT(outMetadata->IsEmpty()); // caller must pass empty metadata
if (!Preferences::GetBool("security.sri.enable", false)) {
SRILOG(("SRICheck::IntegrityMetadata, sri is disabled (pref)"));
return NS_ERROR_SRI_DISABLED;
}
// put a reasonable bound on the length of the metadata
NS_ConvertUTF16toUTF8 metadataList(aMetadataList);
if (metadataList.Length() > SRICheck::MAX_METADATA_LENGTH) {
metadataList.Truncate(SRICheck::MAX_METADATA_LENGTH);
}
MOZ_ASSERT(metadataList.Length() <= aMetadataList.Length());
// the integrity attribute is a list of whitespace-separated hashes
// and options so we need to look at them one by one and pick the
// strongest (valid) one
nsCWhitespaceTokenizer tokenizer(metadataList);
nsAutoCString token;
for (uint32_t i=0; tokenizer.hasMoreTokens() &&
i < SRICheck::MAX_METADATA_TOKENS; ++i) {
token = tokenizer.nextToken();
SRIMetadata metadata(token);
if (metadata.IsMalformed()) {
NS_ConvertUTF8toUTF16 tokenUTF16(token);
nsTArray<nsString> params;
params.AppendElement(tokenUTF16);
aReporter->AddConsoleReport(nsIScriptError::warningFlag,
NS_LITERAL_CSTRING("Sub-resource Integrity"),
nsContentUtils::eSECURITY_PROPERTIES,
aSourceFileURI, 0, 0,
NS_LITERAL_CSTRING("MalformedIntegrityHash"),
const_cast<const nsTArray<nsString>&>(params));
} else if (!metadata.IsAlgorithmSupported()) {
nsAutoCString alg;
metadata.GetAlgorithm(&alg);
NS_ConvertUTF8toUTF16 algUTF16(alg);
nsTArray<nsString> params;
params.AppendElement(algUTF16);
aReporter->AddConsoleReport(nsIScriptError::warningFlag,
NS_LITERAL_CSTRING("Sub-resource Integrity"),
nsContentUtils::eSECURITY_PROPERTIES,
aSourceFileURI, 0, 0,
NS_LITERAL_CSTRING("UnsupportedHashAlg"),
const_cast<const nsTArray<nsString>&>(params));
}
nsAutoCString alg1, alg2;
if (MOZ_LOG_TEST(SRILogHelper::GetSriLog(), mozilla::LogLevel::Debug)) {
outMetadata->GetAlgorithm(&alg1);
metadata.GetAlgorithm(&alg2);
}
if (*outMetadata == metadata) {
SRILOG(("SRICheck::IntegrityMetadata, alg '%s' is the same as '%s'",
alg1.get(), alg2.get()));
*outMetadata += metadata; // add new hash to strongest metadata
} else if (*outMetadata < metadata) {
SRILOG(("SRICheck::IntegrityMetadata, alg '%s' is weaker than '%s'",
alg1.get(), alg2.get()));
*outMetadata = metadata; // replace strongest metadata with current
}
}
outMetadata->mIntegrityString = aMetadataList;
if (MOZ_LOG_TEST(SRILogHelper::GetSriLog(), mozilla::LogLevel::Debug)) {
if (outMetadata->IsValid()) {
nsAutoCString alg;
outMetadata->GetAlgorithm(&alg);
SRILOG(("SRICheck::IntegrityMetadata, using a '%s' hash", alg.get()));
} else if (outMetadata->IsEmpty()) {
SRILOG(("SRICheck::IntegrityMetadata, no metadata"));
} else {
SRILOG(("SRICheck::IntegrityMetadata, no valid metadata found"));
}
}
return NS_OK;
}
/* static */ nsresult
SRICheck::VerifyIntegrity(const SRIMetadata& aMetadata,
nsIUnicharStreamLoader* aLoader,
const nsAString& aString,
const nsACString& aSourceFileURI,
nsIConsoleReportCollector* aReporter)
{
NS_ENSURE_ARG_POINTER(aLoader);
NS_ENSURE_ARG_POINTER(aReporter);
nsCOMPtr<nsIChannel> channel;
aLoader->GetChannel(getter_AddRefs(channel));
if (MOZ_LOG_TEST(SRILogHelper::GetSriLog(), mozilla::LogLevel::Debug)) {
nsAutoCString requestURL;
nsCOMPtr<nsIURI> originalURI;
if (channel &&
NS_SUCCEEDED(channel->GetOriginalURI(getter_AddRefs(originalURI))) &&
originalURI) {
originalURI->GetAsciiSpec(requestURL);
}
SRILOG(("SRICheck::VerifyIntegrity (unichar stream)"));
}
SRICheckDataVerifier verifier(aMetadata, aSourceFileURI, aReporter);
nsresult rv;
nsDependentCString rawBuffer;
rv = aLoader->GetRawBuffer(rawBuffer);
NS_ENSURE_SUCCESS(rv, rv);
rv = verifier.Update(rawBuffer.Length(), (const uint8_t*)rawBuffer.get());
NS_ENSURE_SUCCESS(rv, rv);
return verifier.Verify(aMetadata, channel, aSourceFileURI, aReporter);
}
//////////////////////////////////////////////////////////////
//
//////////////////////////////////////////////////////////////
SRICheckDataVerifier::SRICheckDataVerifier(const SRIMetadata& aMetadata,
const nsACString& aSourceFileURI,
nsIConsoleReportCollector* aReporter)
: mCryptoHash(nullptr),
mBytesHashed(0),
mInvalidMetadata(false),
mComplete(false)
{
MOZ_ASSERT(!aMetadata.IsEmpty()); // should be checked by caller
// IntegrityMetadata() checks this and returns "no metadata" if
// it's disabled so we should never make it this far
MOZ_ASSERT(Preferences::GetBool("security.sri.enable", false));
MOZ_ASSERT(aReporter);
if (!aMetadata.IsValid()) {
nsTArray<nsString> params;
aReporter->AddConsoleReport(nsIScriptError::warningFlag,
NS_LITERAL_CSTRING("Sub-resource Integrity"),
nsContentUtils::eSECURITY_PROPERTIES,
aSourceFileURI, 0, 0,
NS_LITERAL_CSTRING("NoValidMetadata"),
const_cast<const nsTArray<nsString>&>(params));
mInvalidMetadata = true;
return; // ignore invalid metadata for forward-compatibility
}
aMetadata.GetHashType(&mHashType, &mHashLength);
}
nsresult
SRICheckDataVerifier::EnsureCryptoHash()
{
MOZ_ASSERT(!mInvalidMetadata);
if (mCryptoHash) {
return NS_OK;
}
nsresult rv;
nsCOMPtr<nsICryptoHash> cryptoHash =
do_CreateInstance("@mozilla.org/security/hash;1", &rv);
NS_ENSURE_SUCCESS(rv, rv);
rv = cryptoHash->Init(mHashType);
NS_ENSURE_SUCCESS(rv, rv);
mCryptoHash = cryptoHash;
return NS_OK;
}
nsresult
SRICheckDataVerifier::Update(uint32_t aStringLen, const uint8_t* aString)
{
NS_ENSURE_ARG_POINTER(aString);
if (mInvalidMetadata) {
return NS_OK; // ignoring any data updates, see mInvalidMetadata usage
}
nsresult rv;
rv = EnsureCryptoHash();
NS_ENSURE_SUCCESS(rv, rv);
mBytesHashed += aStringLen;
return mCryptoHash->Update(aString, aStringLen);
}
nsresult
SRICheckDataVerifier::Finish()
{
if (mInvalidMetadata || mComplete) {
return NS_OK; // already finished or invalid metadata
}
nsresult rv;
rv = EnsureCryptoHash(); // we need computed hash even for 0-length data
NS_ENSURE_SUCCESS(rv, rv);
rv = mCryptoHash->Finish(false, mComputedHash);
mCryptoHash = nullptr;
mComplete = true;
return rv;
}
nsresult
SRICheckDataVerifier::VerifyHash(const SRIMetadata& aMetadata,
uint32_t aHashIndex,
const nsACString& aSourceFileURI,
nsIConsoleReportCollector* aReporter)
{
NS_ENSURE_ARG_POINTER(aReporter);
nsAutoCString base64Hash;
aMetadata.GetHash(aHashIndex, &base64Hash);
SRILOG(("SRICheckDataVerifier::VerifyHash, hash[%u]=%s", aHashIndex, base64Hash.get()));
nsAutoCString binaryHash;
if (NS_WARN_IF(NS_FAILED(Base64Decode(base64Hash, binaryHash)))) {
nsTArray<nsString> params;
aReporter->AddConsoleReport(nsIScriptError::errorFlag,
NS_LITERAL_CSTRING("Sub-resource Integrity"),
nsContentUtils::eSECURITY_PROPERTIES,
aSourceFileURI, 0, 0,
NS_LITERAL_CSTRING("InvalidIntegrityBase64"),
const_cast<const nsTArray<nsString>&>(params));
return NS_ERROR_SRI_CORRUPT;
}
uint32_t hashLength;
int8_t hashType;
aMetadata.GetHashType(&hashType, &hashLength);
if (binaryHash.Length() != hashLength) {
nsTArray<nsString> params;
aReporter->AddConsoleReport(nsIScriptError::errorFlag,
NS_LITERAL_CSTRING("Sub-resource Integrity"),
nsContentUtils::eSECURITY_PROPERTIES,
aSourceFileURI, 0, 0,
NS_LITERAL_CSTRING("InvalidIntegrityLength"),
const_cast<const nsTArray<nsString>&>(params));
return NS_ERROR_SRI_CORRUPT;
}
if (MOZ_LOG_TEST(SRILogHelper::GetSriLog(), mozilla::LogLevel::Debug)) {
nsAutoCString encodedHash;
nsresult rv = Base64Encode(mComputedHash, encodedHash);
if (NS_SUCCEEDED(rv)) {
SRILOG(("SRICheckDataVerifier::VerifyHash, mComputedHash=%s",
encodedHash.get()));
}
}
if (!binaryHash.Equals(mComputedHash)) {
SRILOG(("SRICheckDataVerifier::VerifyHash, hash[%u] did not match", aHashIndex));
return NS_ERROR_SRI_CORRUPT;
}
SRILOG(("SRICheckDataVerifier::VerifyHash, hash[%u] verified successfully", aHashIndex));
return NS_OK;
}
nsresult
SRICheckDataVerifier::Verify(const SRIMetadata& aMetadata,
nsIChannel* aChannel,
const nsACString& aSourceFileURI,
nsIConsoleReportCollector* aReporter)
{
NS_ENSURE_ARG_POINTER(aReporter);
if (MOZ_LOG_TEST(SRILogHelper::GetSriLog(), mozilla::LogLevel::Debug)) {
nsAutoCString requestURL;
nsCOMPtr<nsIRequest> request;
request = do_QueryInterface(aChannel);
request->GetName(requestURL);
SRILOG(("SRICheckDataVerifier::Verify, url=%s (length=%lu)",
requestURL.get(), mBytesHashed));
}
nsresult rv = Finish();
NS_ENSURE_SUCCESS(rv, rv);
nsCOMPtr<nsILoadInfo> loadInfo = aChannel->GetLoadInfo();
NS_ENSURE_TRUE(loadInfo, NS_ERROR_FAILURE);
LoadTainting tainting = loadInfo->GetTainting();
if (NS_FAILED(IsEligible(aChannel, tainting, aSourceFileURI, aReporter))) {
return NS_ERROR_SRI_NOT_ELIGIBLE;
}
if (mInvalidMetadata) {
return NS_OK; // ignore invalid metadata for forward-compatibility
}
for (uint32_t i = 0; i < aMetadata.HashCount(); i++) {
if (NS_SUCCEEDED(VerifyHash(aMetadata, i, aSourceFileURI, aReporter))) {
return NS_OK; // stop at the first valid hash
}
}
nsAutoCString alg;
aMetadata.GetAlgorithm(&alg);
NS_ConvertUTF8toUTF16 algUTF16(alg);
nsTArray<nsString> params;
params.AppendElement(algUTF16);
aReporter->AddConsoleReport(nsIScriptError::errorFlag,
NS_LITERAL_CSTRING("Sub-resource Integrity"),
nsContentUtils::eSECURITY_PROPERTIES,
aSourceFileURI, 0, 0,
NS_LITERAL_CSTRING("IntegrityMismatch"),
const_cast<const nsTArray<nsString>&>(params));
return NS_ERROR_SRI_CORRUPT;
}
uint32_t
SRICheckDataVerifier::DataSummaryLength()
{
MOZ_ASSERT(!mInvalidMetadata);
return sizeof(mHashType) + sizeof(mHashLength) + mHashLength;
}
uint32_t
SRICheckDataVerifier::EmptyDataSummaryLength()
{
return sizeof(int8_t) + sizeof(uint32_t);
}
nsresult
SRICheckDataVerifier::DataSummaryLength(uint32_t aDataLen, const uint8_t* aData, uint32_t* length)
{
*length = 0;
NS_ENSURE_ARG_POINTER(aData);
// we expect to always encode an SRI, even if it is empty or incomplete
if (aDataLen < EmptyDataSummaryLength()) {
SRILOG(("SRICheckDataVerifier::DataSummaryLength, encoded length[%u] is too small", aDataLen));
return NS_ERROR_SRI_IMPORT;
}
// decode the content of the buffer
size_t offset = sizeof(mHashType);
size_t len = *reinterpret_cast<const decltype(mHashLength)*>(&aData[offset]);
offset += sizeof(mHashLength);
SRIVERBOSE(("SRICheckDataVerifier::DataSummaryLength, header {%x, %x, %x, %x, %x, ...}",
aData[0], aData[1], aData[2], aData[3], aData[4]));
if (offset + len > aDataLen) {
SRILOG(("SRICheckDataVerifier::DataSummaryLength, encoded length[%u] overflow the buffer size", aDataLen));
SRIVERBOSE(("SRICheckDataVerifier::DataSummaryLength, offset[%u], len[%u]",
uint32_t(offset), uint32_t(len)));
return NS_ERROR_SRI_IMPORT;
}
*length = uint32_t(offset + len);
return NS_OK;
}
nsresult
SRICheckDataVerifier::ImportDataSummary(uint32_t aDataLen, const uint8_t* aData)
{
MOZ_ASSERT(!mInvalidMetadata); // mHashType and mHashLength should be valid
MOZ_ASSERT(!mCryptoHash); // EnsureCryptoHash should not have been called
NS_ENSURE_ARG_POINTER(aData);
if (mInvalidMetadata) {
return NS_OK; // ignoring any data updates, see mInvalidMetadata usage
}
// we expect to always encode an SRI, even if it is empty or incomplete
if (aDataLen < DataSummaryLength()) {
SRILOG(("SRICheckDataVerifier::ImportDataSummary, encoded length[%u] is too small", aDataLen));
return NS_ERROR_SRI_IMPORT;
}
SRIVERBOSE(("SRICheckDataVerifier::ImportDataSummary, header {%x, %x, %x, %x, %x, ...}",
aData[0], aData[1], aData[2], aData[3], aData[4]));
// decode the content of the buffer
size_t offset = 0;
if (*reinterpret_cast<const decltype(mHashType)*>(&aData[offset]) != mHashType) {
SRILOG(("SRICheckDataVerifier::ImportDataSummary, hash type[%d] does not match[%d]",
*reinterpret_cast<const decltype(mHashType)*>(&aData[offset]),
mHashType));
return NS_ERROR_SRI_UNEXPECTED_HASH_TYPE;
}
offset += sizeof(mHashType);
if (*reinterpret_cast<const decltype(mHashLength)*>(&aData[offset]) != mHashLength) {
SRILOG(("SRICheckDataVerifier::ImportDataSummary, hash length[%d] does not match[%d]",
*reinterpret_cast<const decltype(mHashLength)*>(&aData[offset]),
mHashLength));
return NS_ERROR_SRI_UNEXPECTED_HASH_TYPE;
}
offset += sizeof(mHashLength);
// copy the hash to mComputedHash, as-if we had finished streaming the bytes
mComputedHash.Assign(reinterpret_cast<const char*>(&aData[offset]), mHashLength);
mCryptoHash = nullptr;
mComplete = true;
return NS_OK;
}
nsresult
SRICheckDataVerifier::ExportDataSummary(uint32_t aDataLen, uint8_t* aData)
{
MOZ_ASSERT(!mInvalidMetadata); // mHashType and mHashLength should be valid
MOZ_ASSERT(mComplete); // finished streaming
NS_ENSURE_ARG_POINTER(aData);
NS_ENSURE_TRUE(aDataLen >= DataSummaryLength(), NS_ERROR_INVALID_ARG);
// serialize the hash in the buffer
size_t offset = 0;
*reinterpret_cast<decltype(mHashType)*>(&aData[offset]) = mHashType;
offset += sizeof(mHashType);
*reinterpret_cast<decltype(mHashLength)*>(&aData[offset]) = mHashLength;
offset += sizeof(mHashLength);
SRIVERBOSE(("SRICheckDataVerifier::ExportDataSummary, header {%x, %x, %x, %x, %x, ...}",
aData[0], aData[1], aData[2], aData[3], aData[4]));
// copy the hash to mComputedHash, as-if we had finished streaming the bytes
nsCharTraits<char>::copy(reinterpret_cast<char*>(&aData[offset]),
mComputedHash.get(), mHashLength);
return NS_OK;
}
nsresult
SRICheckDataVerifier::ExportEmptyDataSummary(uint32_t aDataLen, uint8_t* aData)
{
NS_ENSURE_ARG_POINTER(aData);
NS_ENSURE_TRUE(aDataLen >= EmptyDataSummaryLength(), NS_ERROR_INVALID_ARG);
// serialize an unknown hash in the buffer, to be able to skip it later
size_t offset = 0;
*reinterpret_cast<decltype(mHashType)*>(&aData[offset]) = 0;
offset += sizeof(mHashType);
*reinterpret_cast<decltype(mHashLength)*>(&aData[offset]) = 0;
offset += sizeof(mHashLength);
SRIVERBOSE(("SRICheckDataVerifier::ExportEmptyDataSummary, header {%x, %x, %x, %x, %x, ...}",
aData[0], aData[1], aData[2], aData[3], aData[4]));
return NS_OK;
}
} // namespace dom
} // namespace mozilla
Reference in New Issue View Git Blame Copy Permalink